that either John or Paul will suffer more in occupation A than in B. The upshot of the matter is that Adam Smith’s proposition implies only our ability to compare the _disutility_ (using this word in the sense it ought to have) of different tasks. A task is objective, consisting in certain objective results to be effected under certain objective conditions. When the objective characteristics of a task necessitate subjective discomfort in the person who performs it, the task or employment possesses _disutility_, which is thus a concept the opposite of _utility_. If within a competing group employment A affords a higher wage than employment B, because its _disutility_ is higher, the result is brought about not, in the first instance, through the perception by the workers that certain individual persons work harder than other individual persons, but through the perception that any normal individual for himself would work harder at the task A than at the task B. The possibility of comparison is implied merely between the “pains” of the same person, though there are common forms of expression which imply more. We may conclude, then, that there is a perfectly legitimate sense in which we can compare the subjective costliness of commodities produced in society by entirely different groups of persons. And no one doubts that the day’s product of a coal miner has a higher disutility cost than the day’s product of a farmer. When we find the statement in an economic treatise that the exchange values of commodities are ultimately regulated by their subjective cost, it is to be assumed that the meaning is the same as that which would be expressed with greater precision by using the word costliness. With the explanations already offered we may henceforth follow common usage and employ the mere word cost. There are two distinct ways of reckoning the pain cost of a commodity, namely, (1) as total cost; (2) as marginal cost. Ricardo reckoned cost according to a hybrid method. The _total subjective cost_ of a good consists in all the discomforts of labor and abstinence actually endured in the past to produce it. Taking the factor of labor alone for illustration, it includes the cost of the labor directly applied to the good, and of the labor indirectly applied by being directly applied to the raw material and machinery which are used up in its making. The machinery, however, has always been made at the combined expense of labor and of using up formerly existing tools and machinery; and the latter tools and machines had a labor cost. A product’s total cost may include, perhaps, one one-hundredth of the labor cost of the first generation of certain machinery used in its production, and as we go back, one one-millionth of the second generation;[251] and the total labor cost of any commodity thus goes back no man knows how far. Therefore, the total labor cost alone of a good (to say nothing of the abstinence element) is an extremely indefinite quantity; and